Rhododendron indicum plant named ‘Julonso’

ABSTRACT

A new and distinct variety of semi-dwarf azalea originated from a branch sport of ‘Crimson Queen’. The new variety possesses a unique blush red foliage (185A-B, greyed-purple group), on new growth while the older leaves approximate N189-A &amp; -B, Grayed-Green Group.

Scientific name: Rhododendron indicum.

Cultivar or variety demonimation: ‘Julonso’.

The plant belongs to a group of azaleas called the “Southern Indianazaleas” or “indicas” that are hybrids derived from various species ofRhododendron or derived directly from various species in that genus.Rhododendron indicum (L.) Sweet, although often given as the scientificname for this group of plants, has had little or no part in theparentage of the indicas. Most indicas are descendents of Rhododendronsimsii Planch. R. mucronatum G. Don and/or R. pulchrum Sweet or theirhybrids; in the industry, however, the accepted parentage is that ofRhododendron indicum.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct variety of evergreenazaleas botanically known as Rhododendron indicum. Richard Odomdiscovered this new azalea variety in Forest Hill, La., hereinafterreferred to as ‘Julonso’ as a naturally occurring branch sport of anAzalea ‘Crimson Queen’ (U.S. Plant Pat. No. 14,343), which is related toAzalea ‘Red Formosa’ an unpatented azalea that is well-known in thetrade in zones 7-9. For comparison purposes, ‘Crimson Queen’ leafcharacteristics are as follows: upper surface, greyed-purple group,187-A, lower surface, greyed-purple group 184-B, while ‘Red Formosa’characteristics are as follows: leaves upper surface, grayed-greengroup, N189A; leaves lower surface, green group, 138A; stem coloration138-B Green group; bark coloration, 177-B Grayed-orange group; petiolecoloration 138-B, 138-C Green Group.

Tip cuttings were taken from branches of ‘Crimson Queen’ that appearedto have a variation in coloring across the leaf surface. Cuttings werethen taken from subsequent plants as they matured. All work wasundertaken at a nursery in Forest Hill, La. After several generations ofasexual propagation from rooting cuttings, the present plant has beendeveloped with unique coloration and semi-dwarf growth habit.

Plant cuttings are allowed to root and grow in a 2.25 inch diameter(rosecup) container for 6-8 months, at which time the plant is about 3inches in height, and is then transferred to a one gallon container.After an additional 10-12 months of growth, the plant is about 8-10inches in height and about 8-10 inches in spread. At this time, theplant is sufficiently large for commercial sale as a one gallon plant.If larger plants are desired for commercial sale, the plant can bere-potted from the one gallon container to a three gallon container. Anadditional 8-10 months of growth in the three gallon container isgenerally needed to produce a commercial three gallon container plant,at about 18 inches in height and 20-22 inches in spread.

Asexual propagation of the new plant by rooting cuttings has been underMr. Odom's direction in Forest Hill, La. Several generations of the newplant have been evaluated and the distinctive characteristics of theplant have remained stable. The plant cannot be reproduced true fromseed.

SUMMARY OF THE INVENTION

‘Julonso’ a semi-dwarf indica azalea. Growth habit: Shape of the plantat maturity: Broad compact, mound-forming shrubs uniform and outwardlyspreading plant habit; moderately vigorous growth habit and denselyfoliated. Individuals observed at about 2.5 years showed approximately15 to 20 inches tall and 17 to 22 inches broad. A mature plant is 4-6feet high and 4-5 feet wide. Crimson (greyed purple 187-A) on the upperand lower surfaces of the leaves; shades of green somewhat more evidenton the upper surface, less so on the lower surfaces of the leaves. Thecrimson color is more intense on the new foliage and diminishes somewhatas the leaves age resulting in the older foliage having a deepcrimson/green hue. Color differs significantly from standard ‘RedFormosa’ which has bright green foliage at all stages of maturity. Veinsof ‘Julonso’, especially the midvein and secondary veins, on theunderside of the leaves retain the crimson color as the leaves growolder. The cultivar has a semi-compact growth habitat. The cultivar hasa red-purple flower color similar to that of Azalea ‘Red Formosa’.

The following are the most outstanding and distinguishingcharacteristics of this new cultivar when grown under normalhorticultural practices in Forest Hill, La.

-   -   1. The unique foliage coloration, color (mature leaves)        greyed-green group, N189-A &-B 187-A on the upper leaf surface        with more green apparent near the mid veins.    -   2. Easily propagated with semi-hardwood cuttings in late spring        through the summer.    -   3. Fast growth rate under normal fertilization and moisture        conditions.    -   4. Upright, dense and globose in nature.    -   5. Small semi-compact growth habitat, similar to the ‘Crimson        Queen’.    -   6. Makes a good container plant for under mid height or low        height windows.    -   7. Useful in more confined landscape areas.    -   8. Groupings within landscape beds.

DESCRIPTION OF THE DRAWINGS

This new azalea variety is illustrated by the accompanying photographicprints in which:

FIG. 1 is a view of the new azalea plant in three gallon, showing theplant at about 3 years of age.

FIG. 2 is a close up view of the bloom of the new azalea.

FIG. 3 shows a stem cuting of the new azalea showing the leaves topsurface and underside surface.

FIG. 4. is a top view of the plant shown in FIG. 1.

The colors shown are as true as is reasonably possible to obtain byconventional photographic procedures. The colors of the various plantparts are defined with reference to The Royal Horticultural SocietyColour Chart (2001). Description of colors in ordinary terms arepresented where appropriate for clarity in meaning. Colors in thephotographs may appear different than actual colors due to lightreflectance. Color values cited in the Botanical Description of thePlant accurately describe the actual colors of the new azalea.

DETAILED BOTANICAL DESCRIPTION

The following is a detailed description of the new variety of azaleabased on observations made of plants grown in wholesale commercialproduction practices, in greenhouses, and in established landscapeplantings in Forest Hill, La., and was compiled with the assistance ofDr. Lowell E. Urbatsch, Director of the LSU Herbarium, Louisiana StateUniversity.

BOTANICAL DESCRIPTION OF THE PLANT

-   Branching habit: Sympodial (branching without a main axis but with    many, more or less, equal laterals). Seven to twelve stems are    evident at or near ground level that branch and re-branch frequently    and at close intervals. Branches are ascending or arcuate-ascending    to upright. Branching may increase with maturity. Branch    characteristics (on mature growth of the current season): branch    length, 5-20 cm; branch diameter, 3-7 mm; internode length, 1-20 mm,    branch strength is strong as is stem strength.-   Characteristics of the plant in winter dormancy: During the winter,    the plants are evergreen, i.e., the leaves remain on the stems. No    signs of growth or flowering are evident during winter. Hardiness is    expected to be the same as ‘Red Formosa’ cultivars, that is, hardy    in zones 7-9.

A. BARK

Younger stems supporting flowers and newly formed leaves were rated as185-A in the Grayed Purple Group; somewhat older ones were darker andrated 178-A Grayed Red Group; and the oldest of the woody stems wererated 201-A and -B, Grayed Group. These lower stems are rarely visibledue to the compact leafy nature of the plants and they contribute littleto its ornamental qualities.

B. INFLORESCENCE AND FLOWERS

-   Infloresence: Racemose; flowers appearing individually or in    clusters of 2 or 3 each supported by pedicel (flower stalk) on leafy    branches.-   Flower buds: Flower buds just before anthesis are 5-angled and about    1.5 to 1.8 inches in length, similar to ‘Red Formosa’ cultivars.    Corolla color of the flower bud is 64-B in the Red-Purple group.    Rate of opening just after bud corolla becomes visible is about 2-3    days but rate is variable with temperature, sunlight, and possible    other conditions. Corolla color becomes visible when bud is about 12    mm long and 8 mm wide. Flower bud shape is ovoid when viewed    dosal-ventrally. When about 17 mm long and 10 mm wide the petals    become visible and at about 4 cm long and 1.5-2 cm wide when the    petals begin to open. In side view bud bulges slightly outward,    inner surface is slightly concave. Overall, the bud has a somewhat    falcate shape. As viewed from the top or in cross- section bud is    slightly 5-lobed.-   Flowers: Arranged singlely or mostly in groups of 2-3 flowers at    stem terminus; flowers face outward and upward. The petals or    corolla are 5 in number and basally fused forming a corolla tube    about 1 to 1.4 inches in length and width; petal appearance is    satiny; texture is smooth; petals are spatulate (obovate) with    rounded apex and 2.2-3 inches long and width from lobe tip to lobe    tip about 2.5 to 3.5 inches. The lobes measured from circa 1 to 1.25    inches long to about 1-1.3 inches wide. The corolla margins are    minutely and regularly undulate or ruffled. Corollas compare    favorably with 64-B in the Red-Purple group. Mature flowers range    from appoximately 3-4 inches in diameter and about 2-3 inches in    length.-   Sepals: The whorl of sepals (collectively the calyx) outside of the    corolla consists of a five lobed calyx, and measures approximately ¼    inch in length. Individually, the lobes are lanceolate and fused to    one another only at their bases; they range from 7-10 mm long and    3-4 mm wide. They are yellowish green, approximately 141-C, in the    Green Group of The R.H.S. Colour Chart and contribute little to the    ornamental qualities of the flowers. Sepals are moderately pubescent    abaxially (outer surface) and glabrous adaxially (inner surface are    elliptic in shape and their margins are entire and the apex is    acute. In zone 8, flowering season is approximately early April    through early to mid May.-   Reproductive organs: While insignificant in size, the filaments of    stamens nevertheless are intensely colored (60-B, Red-Purple Group,    fan 2); the anthers are much darker (N-77A, Purple Group, fan 2).    They number 9-10 per flower in the specimens examined and have a    filament length of from 1.2 to 2 inches (2.8-5.4 cm). The anthers    are about 1/16 of an inch long (1.5-2 mm) and each releases pollen    through a terminal pore. They are much darker than the filaments    (N-77, Purple Group, fan 2). Gynoecium appears to consist of 5 fused    carpels. The ovary is densely pubescent (sericeous) with the hairs    obscuring ovary surface; hairs are shiny and closest to 60-C in    color; ovary shape is ovoid and about 5 mm long. The style is about    4.5-5 cm long, 1.5 mm in diameter and near 59-B in color. The stigma    is truncate (i.e., having a flat surface) to slightly convex and    circular to slightly lobed in end view with a diameter of 1.5 mm.-   Peduncle: Peduncle (i.e., the stalk supporting a cluster of flowers)    length is from 15-20 mm long and about 2 mm in diameter; it is    somewhat flexible and it provides strong support for the flower; it    is moderately pubescent with uniseriate hairs; and near 60-B (fan 2)    in color.

C. LEAVES

-   Arrangement: Leaves are alternate, that is one leaf per node. Leaves    are spaced about 1/16 to about 1 inch apart along the stems    (internode length). Leaf stalk (petiole) about ⅛ to ⅜ inches long.-   Leaf shape: Leaves elliptic to oblanceolate in outline; apices acute    to acuminate; bases cuneate to rounded. Margins are entire although    generally bordered with ciliate hairs. Leaves are spaced about ¼ to    3/24 inches apart along the stems. Leaf stalk (petiole) about 3/16    to ½ inches long.-   Leaf size: ½ to 1 inch broad and 1 to 3 inches long including the    petiole and ¾ to 1.5 inches wide.-   Leaf color: Crimson (185A-B, greyed-purple group), on the upper and    lower surfaces; shades of green N189-A & -B, Grayed-Green Group,    somewhat more evident on the upper surface more so toward the    midvein and leaf base, less so marginally and on the lower surface.    Intensity of color is greatest apically and marginally. The crimson    color is more intense on the new foliage and diminishes somewhat as    the leaves age resulting in the older foliage having a deep    crimson/green hue. Color ratings for new growth leaves are 185-A &    B, Grayed-Purple Group, while the older leaves approximate N189-A &    -B, Grayed-Green Group, on the upper surface with more green    apparent near the mid veins. Color differs significantly from    standard ‘Red Formosa’ which has bright green foliage at all stages    of maturity. Leaf Veins, especially the midvein and secondary veins,    on the leaf undersides of the present cultivar retain the crimson    color (185A-B, Greyed-Purple Group) with age. Veins on both leaf    surfaces with age may become a greyed-orange color, 167 C-D,    Greyed-Orange Group.-   Indumentum: The indumentum or plant hairs (trichomes) are hirsute in    nature, i.e. the individual hairs are uniseriate, slender, tapering    at the tip and arising more or less perpendicular to the epidermis,    and becoming somewhat flexuous slightly above the leaf surface. The    hairs give the leaves and twigs a somewhat bristly texture. The same    type of hairs are present on both the upper and lower leaf surfaces.    In terms of density the indumentum is characterized as being    moderately pubescent with the hairs being spaced about 1/32 inch    (0.5 mm) apart. On the lower surface the hairs are somewhat more    closely spaced along the veins and petioles. Indumentum on the stems    is similar except for the hairs being somewhat more closely spaced    than on the leaf blade surfaces. Its color typically is    greyed-white, 156 B-C, Greyed-White Group, but may become similar to    that of the midvein on older leaves, i.e. 167 C-D, Greyed-Orange    Group.

D. OTHER

-   Fruit: Insignificant.-   Petiole: Length 6-10 mm; diameter 1.5-3 mm wide, 1.5 mm thick;    coloration: upper surface, 138-B Green Group with flecks of 59-A,    Red-Purple Group; lower surface 59-A Red Purple Group with flecks of    138 B Green Group.-   Fragrance: None evident.-   Taste: Not relevant.-   Disease resistances: Disease resistances. — No known Azalea diseases    observed to date on plants grown under commercial conditions.    Expected to be similar to ‘Red Formosa’ cultivars — resistant to    flower and leaf gall, caused by Exobasidium vaccinii and root rot    caused Phytophthora cinnamomi; susceptible to Lace bug and to petal    blight caused by Ovulinia azalea.-   Productivity of flowers and leaves: Similar to ‘Red Formosa’    cultivars, but flower production is slightly more profuse.-   Vigor: Similar to ‘Red Formosa’ cultivars, hardy in zones 7-9.

The invention claimed is:
 1. A new and distinct variety of azalea plant,substantially as shown and described.